"For the last few days I've been so nervous," she admits. "Even though I've been modelling for years, it's my first season doing any shows. It's nerve-racking.
Especially in Milan, where every girl is 5ft 11in [1.8m] - I do feel that height-ist attitude. But I've got Cara [Delevingne], who's one of my best friends and the same height as me. Kate Moss is the same height as well. We're few and far between, short girls."
To be clear, at 1.7m Jagger is far from diminutive. However, walking in the Just Cavalli autumn/winter show the day before I meet her was a rare gig. She is far more often featured in advertising campaigns - as well as Hudson, she stars in ads for Rimmel and fragrance Just Cavalli For Her - and editorial shoots for publications such as Vogue, Harper's Bazaar, Love and i-D.
"I really enjoy doing beauty because I'm not as tall as the other girls," she confides. "I feel like I'm a bit better at it. But I actually really enjoy doing the shows, because I do a lot of interviews and things like this party. It's nice when you're doing modelling to do every aspect of it, to be with the other girls and to get to hang out backstage. It's quite fun.
"But then saying that, I'm not doing five shows a day for every Fashion Week. If I did I'd probably have a different heart. I'm not sure."
Much has been made of Jagger's unusual family circumstances. The youngest daughter of Mick Jagger and Texan beauty Jerry Hall, her parents have long had a tumultuous relationship. But Georgia May Jagger seems to have a close relationship with her siblings, including those from her father's previous relationships.
Family is important to the young model, and the influence of Hall - as both mother and model - is evident. "My mum loves that I've followed in her footsteps. She likes to get copies of everything I've done, it's really sweet. She does stuff like putting my campaigns in frames, and I always take them down. It's so embarrassing but she's just being a mum.
You know what they're like.
"Right now, the industry reminds me of when my mum was younger, because the girls are supermodels, they do everything and they have the personality to boot. I do think the industry is changing as far as body types [go]. I feel like a personality and an important face is sticking more than just everyone being the same."
Delevingne, who was the undisputed girl of the season, can certainly attest to that.
"Growing up in the public eye has prepared me a little bit more than some people who are thrown right into the fashion business. I understand how things work," says Jagger, although she admits that the level of interest and access people have in the age of social networking is scary.
"I heard that Cara is going to be my new roommate. That's not even like a real thing. It's not really that funny [to read untrue stories in the press]. That, obviously, is not that bad, but I feel nowadays it's just going downhill really badly with the press, to the point where someone eating a sandwich is news.
"I'm not very good at Twitter, I have to make myself do it, but I don't read all the feed - it freaks me out every time I do. People are really nice but sometimes they're a bit scary."
Part of the skill of a good model is to make the role seem effortless - belying the toll that long hours and extensive travel can take on the lives, and bodies, of young women who, understandably, still want to have fun.
"Even without partying, [the season] is hard. You'll do a job then you'll go to a fitting for another job. I've been up till midnight doing stuff since I've been here - it's intense. I'm not even doing all the shows that some of the girls are, and I feel bad for them because it's crazy. Everyone wants you to look perfect, but you go to bed at 3am and have to get up at 6am.
Jagger says modelling makes her happy but she is preparing for the future. "I might not be modelling forever. I like to live more in the moment. People always ask what you'll be doing in 10 years, which I think is a bit unfair. I don't really want to think about being 31 right now. I can barely think about what time I have to get up tomorrow."
She adds: "I don't have a big plan of what I'm going to do in the future. I'm hoping to start doing more photography, but I haven't had much time because I'm travelling so much. I went to university, but I'm mostly self-taught - I think that's how you figure out everything - just doing it yourself. That's how you figure it out with modelling. You don't just immediately know everything."
As the daughter of a Rolling Stone, Jagger grew up on music tours. "I was always moving around and I always thought I didn't want to do that. I always complain that I want to go home, but then when I'm bored I'll call up my agent and ask, 'How come I'm not going anywhere exciting?' So I like that aspect of the job.
"Sometimes I bring scarves and throw them over the furniture in the hotel room so I feel it's more like home. I get quite into it, though, because I've been travelling around in hotel rooms for a long time, so I like to make them my home.
Sometimes I make them purposefully a bit more messy so it feels like my own room."
That ability to make anywhere feel like home must feel invaluable to Jagger as she travels the world, all the while keeping her feet firmly planted on the ground.
- Independent
